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superlativeform of grunty: most grunty.
Sorry, no etymologies found.
While the GPU isn't the gruntiest (it's just a rebadged 9600GSO), the rest of the specs are impressive.
The good load-out doesn't stop there, either - the GX720 is graced with a 4.1 speaker set-up that is, well, not the gruntiest of mobile sound solutions we've seen, but certainly adequate.